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<FONT color="green">001</FONT>    // Copyright 2008 Waterken Inc. under the terms of the MIT X license<a name="line.1"></a>
<FONT color="green">002</FONT>    // found at http://www.opensource.org/licenses/mit-license.html<a name="line.2"></a>
<FONT color="green">003</FONT>    package org.waterken.syntax.config;<a name="line.3"></a>
<FONT color="green">004</FONT>    <a name="line.4"></a>
<FONT color="green">005</FONT>    import java.io.File;<a name="line.5"></a>
<FONT color="green">006</FONT>    import java.io.OutputStream;<a name="line.6"></a>
<FONT color="green">007</FONT>    import java.lang.reflect.Type;<a name="line.7"></a>
<FONT color="green">008</FONT>    <a name="line.8"></a>
<FONT color="green">009</FONT>    import org.joe_e.array.ByteArray;<a name="line.9"></a>
<FONT color="green">010</FONT>    import org.joe_e.array.ConstArray;<a name="line.10"></a>
<FONT color="green">011</FONT>    import org.joe_e.array.PowerlessArray;<a name="line.11"></a>
<FONT color="green">012</FONT>    import org.joe_e.file.Filesystem;<a name="line.12"></a>
<FONT color="green">013</FONT>    import org.waterken.syntax.Exporter;<a name="line.13"></a>
<FONT color="green">014</FONT>    import org.waterken.syntax.Importer;<a name="line.14"></a>
<FONT color="green">015</FONT>    import org.waterken.syntax.Syntax;<a name="line.15"></a>
<FONT color="green">016</FONT>    import org.waterken.syntax.json.JSONDeserializer;<a name="line.16"></a>
<FONT color="green">017</FONT>    import org.waterken.syntax.json.JSONSerializer;<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    /**<a name="line.19"></a>
<FONT color="green">020</FONT>     * A folder of serialized configuration settings.<a name="line.20"></a>
<FONT color="green">021</FONT>     * &lt;p&gt;<a name="line.21"></a>
<FONT color="green">022</FONT>     * This class provides convenient access to a folder of JSON files; each of<a name="line.22"></a>
<FONT color="green">023</FONT>     * which represents a particular configuration setting. The class provides<a name="line.23"></a>
<FONT color="green">024</FONT>     * methods for {@linkplain #init initializing} and {@linkplain #read reading}<a name="line.24"></a>
<FONT color="green">025</FONT>     * these settings.<a name="line.25"></a>
<FONT color="green">026</FONT>     * &lt;/p&gt;<a name="line.26"></a>
<FONT color="green">027</FONT>     * &lt;p&gt;<a name="line.27"></a>
<FONT color="green">028</FONT>     * For example, consider a folder with contents:<a name="line.28"></a>
<FONT color="green">029</FONT>     * &lt;/p&gt;<a name="line.29"></a>
<FONT color="green">030</FONT>     * &lt;pre&gt;<a name="line.30"></a>
<FONT color="green">031</FONT>     * config/<a name="line.31"></a>
<FONT color="green">032</FONT>     *     - username.json<a name="line.32"></a>
<FONT color="green">033</FONT>     *         { "=" : "tyler.close" }<a name="line.33"></a>
<FONT color="green">034</FONT>     *     - port.json<a name="line.34"></a>
<FONT color="green">035</FONT>     *         { "=" : 8088 }<a name="line.35"></a>
<FONT color="green">036</FONT>     *     - home.json<a name="line.36"></a>
<FONT color="green">037</FONT>     *         {<a name="line.37"></a>
<FONT color="green">038</FONT>     *             "class" : [ "org.example.hypertext.Anchor" ],<a name="line.38"></a>
<FONT color="green">039</FONT>     *             "icon" : "home.png",<a name="line.39"></a>
<FONT color="green">040</FONT>     *             "href" : "http://waterken.sourceforge.net/",<a name="line.40"></a>
<FONT color="green">041</FONT>     *             "tooltip" : "Home page"<a name="line.41"></a>
<FONT color="green">042</FONT>     *         }<a name="line.42"></a>
<FONT color="green">043</FONT>     * &lt;/pre&gt;<a name="line.43"></a>
<FONT color="green">044</FONT>     * &lt;p&gt;<a name="line.44"></a>
<FONT color="green">045</FONT>     * These settings can be read with code:<a name="line.45"></a>
<FONT color="green">046</FONT>     * &lt;/p&gt;<a name="line.46"></a>
<FONT color="green">047</FONT>     * &lt;pre&gt;<a name="line.47"></a>
<FONT color="green">048</FONT>     * final Config config = new Config(new File("config/"),<a name="line.48"></a>
<FONT color="green">049</FONT>     *                                  getClass().getClassLoader());<a name="line.49"></a>
<FONT color="green">050</FONT>     * final String username = config.read("username");<a name="line.50"></a>
<FONT color="green">051</FONT>     * final int port = config.read("port");<a name="line.51"></a>
<FONT color="green">052</FONT>     * final Anchor home = config.read("home");<a name="line.52"></a>
<FONT color="green">053</FONT>     * &lt;/pre&gt;<a name="line.53"></a>
<FONT color="green">054</FONT>     */<a name="line.54"></a>
<FONT color="green">055</FONT>    public final class<a name="line.55"></a>
<FONT color="green">056</FONT>    Config {<a name="line.56"></a>
<FONT color="green">057</FONT>        <a name="line.57"></a>
<FONT color="green">058</FONT>        /**<a name="line.58"></a>
<FONT color="green">059</FONT>         * JSON syntax<a name="line.59"></a>
<FONT color="green">060</FONT>         */<a name="line.60"></a>
<FONT color="green">061</FONT>        static private final Syntax json =<a name="line.61"></a>
<FONT color="green">062</FONT>            new Syntax(".json", new JSONSerializer(), new JSONDeserializer());<a name="line.62"></a>
<FONT color="green">063</FONT>        <a name="line.63"></a>
<FONT color="green">064</FONT>        /**<a name="line.64"></a>
<FONT color="green">065</FONT>         * each known syntax<a name="line.65"></a>
<FONT color="green">066</FONT>         */<a name="line.66"></a>
<FONT color="green">067</FONT>        static private final PowerlessArray&lt;Syntax&gt; known = PowerlessArray.array(<a name="line.67"></a>
<FONT color="green">068</FONT>            json<a name="line.68"></a>
<FONT color="green">069</FONT>        );<a name="line.69"></a>
<FONT color="green">070</FONT>    <a name="line.70"></a>
<FONT color="green">071</FONT>        private   final File root;<a name="line.71"></a>
<FONT color="green">072</FONT>        protected final ClassLoader code;<a name="line.72"></a>
<FONT color="green">073</FONT>        protected final String namespace;<a name="line.73"></a>
<FONT color="green">074</FONT>        protected final Importer connect;<a name="line.74"></a>
<FONT color="green">075</FONT>        protected final File home;<a name="line.75"></a>
<FONT color="green">076</FONT>        protected final PowerlessArray&lt;Syntax&gt; supported;<a name="line.76"></a>
<FONT color="green">077</FONT>        private   final Syntax output;<a name="line.77"></a>
<FONT color="green">078</FONT>        <a name="line.78"></a>
<FONT color="green">079</FONT>        protected       PowerlessArray&lt;String&gt; cacheKeys;<a name="line.79"></a>
<FONT color="green">080</FONT>        protected       ConstArray&lt;Object&gt; cacheValues;<a name="line.80"></a>
<FONT color="green">081</FONT>        <a name="line.81"></a>
<FONT color="green">082</FONT>        /**<a name="line.82"></a>
<FONT color="green">083</FONT>         * Constructs an instance.<a name="line.83"></a>
<FONT color="green">084</FONT>         * @param root      root folder for configuration files<a name="line.84"></a>
<FONT color="green">085</FONT>         * @param code      class loader for serialized objects<a name="line.85"></a>
<FONT color="green">086</FONT>         * @param namespace global identifier for stored object namespace<a name="line.86"></a>
<FONT color="green">087</FONT>         * @param connect   remote reference importer, may be &lt;code&gt;null&lt;/code&gt;<a name="line.87"></a>
<FONT color="green">088</FONT>         * @param home      root folder for a path beginning with &lt;code&gt;~&lt;/code&gt;<a name="line.88"></a>
<FONT color="green">089</FONT>         * @param supported each supported {@linkplain #read input} syntax<a name="line.89"></a>
<FONT color="green">090</FONT>         * @param output    {@linkplain #init output} syntax<a name="line.90"></a>
<FONT color="green">091</FONT>         */<a name="line.91"></a>
<FONT color="green">092</FONT>        public<a name="line.92"></a>
<FONT color="green">093</FONT>        Config(final File root, final ClassLoader code, final String namespace,<a name="line.93"></a>
<FONT color="green">094</FONT>               final Importer connect, final File home,<a name="line.94"></a>
<FONT color="green">095</FONT>               final PowerlessArray&lt;Syntax&gt; supported, final Syntax output) {<a name="line.95"></a>
<FONT color="green">096</FONT>            this.root = root;<a name="line.96"></a>
<FONT color="green">097</FONT>            this.code = code;<a name="line.97"></a>
<FONT color="green">098</FONT>            this.namespace = namespace;<a name="line.98"></a>
<FONT color="green">099</FONT>            this.connect = connect;<a name="line.99"></a>
<FONT color="green">100</FONT>            this.home = home;<a name="line.100"></a>
<FONT color="green">101</FONT>            this.supported = supported;<a name="line.101"></a>
<FONT color="green">102</FONT>            this.output = output;<a name="line.102"></a>
<FONT color="green">103</FONT>            <a name="line.103"></a>
<FONT color="green">104</FONT>            cacheKeys = PowerlessArray.array();<a name="line.104"></a>
<FONT color="green">105</FONT>            cacheValues = ConstArray.array();<a name="line.105"></a>
<FONT color="green">106</FONT>        }<a name="line.106"></a>
<FONT color="green">107</FONT>        <a name="line.107"></a>
<FONT color="green">108</FONT>        /**<a name="line.108"></a>
<FONT color="green">109</FONT>         * Constructs an instance.<a name="line.109"></a>
<FONT color="green">110</FONT>         * @param root      root folder for configuration files<a name="line.110"></a>
<FONT color="green">111</FONT>         * @param code      class loader for serialized objects<a name="line.111"></a>
<FONT color="green">112</FONT>         * @param namespace global identifier for stored object namespace<a name="line.112"></a>
<FONT color="green">113</FONT>         * @param connect   remote reference importer, may be &lt;code&gt;null&lt;/code&gt;<a name="line.113"></a>
<FONT color="green">114</FONT>         * @param home      root folder for a path beginning with &lt;code&gt;~&lt;/code&gt;<a name="line.114"></a>
<FONT color="green">115</FONT>         */<a name="line.115"></a>
<FONT color="green">116</FONT>        public<a name="line.116"></a>
<FONT color="green">117</FONT>        Config(final File root, final ClassLoader code, final String namespace,<a name="line.117"></a>
<FONT color="green">118</FONT>               final Importer connect, final File home) {<a name="line.118"></a>
<FONT color="green">119</FONT>            this(root, code, namespace, connect, home, known, json);<a name="line.119"></a>
<FONT color="green">120</FONT>        }<a name="line.120"></a>
<FONT color="green">121</FONT>        <a name="line.121"></a>
<FONT color="green">122</FONT>        /**<a name="line.122"></a>
<FONT color="green">123</FONT>         * Constructs an instance.<a name="line.123"></a>
<FONT color="green">124</FONT>         * @param root      root folder for configuration files<a name="line.124"></a>
<FONT color="green">125</FONT>         * @param code      class loader for serialized objects<a name="line.125"></a>
<FONT color="green">126</FONT>         */<a name="line.126"></a>
<FONT color="green">127</FONT>        public<a name="line.127"></a>
<FONT color="green">128</FONT>        Config(final File root, final ClassLoader code) {<a name="line.128"></a>
<FONT color="green">129</FONT>            this(root, code, "file:///", null, null);<a name="line.129"></a>
<FONT color="green">130</FONT>        }<a name="line.130"></a>
<FONT color="green">131</FONT>        <a name="line.131"></a>
<FONT color="green">132</FONT>        /**<a name="line.132"></a>
<FONT color="green">133</FONT>         * Reads a configuration setting.<a name="line.133"></a>
<FONT color="green">134</FONT>         * @param &lt;T&gt;   expected value type<a name="line.134"></a>
<FONT color="green">135</FONT>         * @param name  setting name<a name="line.135"></a>
<FONT color="green">136</FONT>         * @return &lt;code&gt;{@link #read(String, Type) read}(name, Object.class)&lt;/code&gt;<a name="line.136"></a>
<FONT color="green">137</FONT>         * @throws Exception    any problem connecting to the identified reference<a name="line.137"></a>
<FONT color="green">138</FONT>         */<a name="line.138"></a>
<FONT color="green">139</FONT>        public @SuppressWarnings("unchecked") &lt;T&gt; T<a name="line.139"></a>
<FONT color="green">140</FONT>        read(final String name) throws Exception {<a name="line.140"></a>
<FONT color="green">141</FONT>            final Object r = read(name, Object.class);<a name="line.141"></a>
<FONT color="green">142</FONT>            return (T)r;<a name="line.142"></a>
<FONT color="green">143</FONT>        }<a name="line.143"></a>
<FONT color="green">144</FONT>        <a name="line.144"></a>
<FONT color="green">145</FONT>        /**<a name="line.145"></a>
<FONT color="green">146</FONT>         * Reads a configuration setting.<a name="line.146"></a>
<FONT color="green">147</FONT>         * &lt;p&gt;<a name="line.147"></a>
<FONT color="green">148</FONT>         * Any &lt;code&gt;name&lt;/code&gt; argument containing a period is assumed to refer<a name="line.148"></a>
<FONT color="green">149</FONT>         * to a configuration file, rather than the serialized object. For example:<a name="line.149"></a>
<FONT color="green">150</FONT>         * &lt;/p&gt;<a name="line.150"></a>
<FONT color="green">151</FONT>         * &lt;pre&gt;<a name="line.151"></a>
<FONT color="green">152</FONT>         * final Config config = &amp;hellip;<a name="line.152"></a>
<FONT color="green">153</FONT>         * final String username = config.read("username");<a name="line.153"></a>
<FONT color="green">154</FONT>         * final File usernameFile = config.read("username.json");<a name="line.154"></a>
<FONT color="green">155</FONT>         * &lt;/pre&gt;<a name="line.155"></a>
<FONT color="green">156</FONT>         * &lt;p&gt;<a name="line.156"></a>
<FONT color="green">157</FONT>         * The configuration folder itself can be accessed using the code:<a name="line.157"></a>
<FONT color="green">158</FONT>         * &lt;/p&gt;<a name="line.158"></a>
<FONT color="green">159</FONT>         * &lt;pre&gt;<a name="line.159"></a>
<FONT color="green">160</FONT>         * final File root = config.read("");<a name="line.160"></a>
<FONT color="green">161</FONT>         * &lt;/pre&gt;<a name="line.161"></a>
<FONT color="green">162</FONT>         * @param &lt;T&gt; expected value type<a name="line.162"></a>
<FONT color="green">163</FONT>         * @param name setting name<a name="line.163"></a>
<FONT color="green">164</FONT>         * @param type expected value type, used as a hint to help deserialization<a name="line.164"></a>
<FONT color="green">165</FONT>         * @return setting value, or &lt;code&gt;null&lt;/code&gt; if not set<a name="line.165"></a>
<FONT color="green">166</FONT>         * @throws Exception any problem connecting to the identified reference<a name="line.166"></a>
<FONT color="green">167</FONT>         */<a name="line.167"></a>
<FONT color="green">168</FONT>        public @SuppressWarnings("unchecked") &lt;T&gt; T<a name="line.168"></a>
<FONT color="green">169</FONT>        read(final String name, final Type type) throws Exception {<a name="line.169"></a>
<FONT color="green">170</FONT>            return (T)sub(root, namespace).apply(name, namespace, type);<a name="line.170"></a>
<FONT color="green">171</FONT>        }<a name="line.171"></a>
<FONT color="green">172</FONT>        <a name="line.172"></a>
<FONT color="green">173</FONT>        protected Importer<a name="line.173"></a>
<FONT color="green">174</FONT>        sub(final File top, final String topspace) { return new Importer() {<a name="line.174"></a>
<FONT color="green">175</FONT>            public Object<a name="line.175"></a>
<FONT color="green">176</FONT>            apply(final String href, final String base,<a name="line.176"></a>
<FONT color="green">177</FONT>                                     final Type... type) throws Exception {<a name="line.177"></a>
<FONT color="green">178</FONT>                if (!topspace.equals(base) || -1 != href.indexOf(':')) {<a name="line.178"></a>
<FONT color="green">179</FONT>                    return connect.apply(href, base, type);<a name="line.179"></a>
<FONT color="green">180</FONT>                }<a name="line.180"></a>
<FONT color="green">181</FONT>                <a name="line.181"></a>
<FONT color="green">182</FONT>                File folder;        // folder containing file<a name="line.182"></a>
<FONT color="green">183</FONT>                String subspace;    // namespace for containing folder<a name="line.183"></a>
<FONT color="green">184</FONT>                String name = href; // simple name<a name="line.184"></a>
<FONT color="green">185</FONT>                if (name.startsWith("~/")) {<a name="line.185"></a>
<FONT color="green">186</FONT>                    folder = Config.this.home;<a name="line.186"></a>
<FONT color="green">187</FONT>                    subspace = Config.this.namespace + "~/";<a name="line.187"></a>
<FONT color="green">188</FONT>                    name = name.substring("~/".length());<a name="line.188"></a>
<FONT color="green">189</FONT>                } else {<a name="line.189"></a>
<FONT color="green">190</FONT>                    folder = top;<a name="line.190"></a>
<FONT color="green">191</FONT>                    subspace = topspace;<a name="line.191"></a>
<FONT color="green">192</FONT>                }<a name="line.192"></a>
<FONT color="green">193</FONT>    <a name="line.193"></a>
<FONT color="green">194</FONT>                // check the cache<a name="line.194"></a>
<FONT color="green">195</FONT>                final String key = subspace + name;<a name="line.195"></a>
<FONT color="green">196</FONT>                for (int i = cacheKeys.length(); 0 != i--;) {<a name="line.196"></a>
<FONT color="green">197</FONT>                    if (cacheKeys.get(i).equals(key)) {<a name="line.197"></a>
<FONT color="green">198</FONT>                        return cacheValues.get(i);<a name="line.198"></a>
<FONT color="green">199</FONT>                    }<a name="line.199"></a>
<FONT color="green">200</FONT>                }<a name="line.200"></a>
<FONT color="green">201</FONT>    <a name="line.201"></a>
<FONT color="green">202</FONT>                // descend to the named file<a name="line.202"></a>
<FONT color="green">203</FONT>                while (true) {<a name="line.203"></a>
<FONT color="green">204</FONT>                    final int i = name.indexOf('/');<a name="line.204"></a>
<FONT color="green">205</FONT>                    if (-1 == i) { break; }<a name="line.205"></a>
<FONT color="green">206</FONT>                    folder = Filesystem.file(folder, name.substring(0, i));<a name="line.206"></a>
<FONT color="green">207</FONT>                    subspace += name.substring(0, i + 1);<a name="line.207"></a>
<FONT color="green">208</FONT>                    name = name.substring(i + 1);<a name="line.208"></a>
<FONT color="green">209</FONT>                }<a name="line.209"></a>
<FONT color="green">210</FONT>                if ("".equals(name)) { return folder; }<a name="line.210"></a>
<FONT color="green">211</FONT>                if (-1 != name.indexOf('.')) {return Filesystem.file(folder, name);}<a name="line.211"></a>
<FONT color="green">212</FONT>    <a name="line.212"></a>
<FONT color="green">213</FONT>                // deserialize the named object<a name="line.213"></a>
<FONT color="green">214</FONT>                Object r = null;<a name="line.214"></a>
<FONT color="green">215</FONT>                for (final Syntax syntax : supported) {<a name="line.215"></a>
<FONT color="green">216</FONT>                    final String filename = name + syntax.ext;<a name="line.216"></a>
<FONT color="green">217</FONT>                    final File file = Filesystem.file(folder, filename);<a name="line.217"></a>
<FONT color="green">218</FONT>                    if (!file.isFile()) { continue; }<a name="line.218"></a>
<FONT color="green">219</FONT>                    r = syntax.deserializer.deserialize(Filesystem.read(file),<a name="line.219"></a>
<FONT color="green">220</FONT>                        sub(folder, subspace), subspace, code,<a name="line.220"></a>
<FONT color="green">221</FONT>                        0 == type.length ? Object.class : type[0]);<a name="line.221"></a>
<FONT color="green">222</FONT>                    break;<a name="line.222"></a>
<FONT color="green">223</FONT>                }<a name="line.223"></a>
<FONT color="green">224</FONT>                cacheKeys = cacheKeys.with(key);<a name="line.224"></a>
<FONT color="green">225</FONT>                cacheValues = cacheValues.with(r);<a name="line.225"></a>
<FONT color="green">226</FONT>                return r;<a name="line.226"></a>
<FONT color="green">227</FONT>            }<a name="line.227"></a>
<FONT color="green">228</FONT>        }; }<a name="line.228"></a>
<FONT color="green">229</FONT>        <a name="line.229"></a>
<FONT color="green">230</FONT>        /**<a name="line.230"></a>
<FONT color="green">231</FONT>         * Initializes a configuration setting.<a name="line.231"></a>
<FONT color="green">232</FONT>         * @param name      setting name<a name="line.232"></a>
<FONT color="green">233</FONT>         * @param value     setting value<a name="line.233"></a>
<FONT color="green">234</FONT>         * @param export    remote reference exporter, may be &lt;code&gt;null&lt;/code&gt;<a name="line.234"></a>
<FONT color="green">235</FONT>         * @throws Exception    any problem persisting the &lt;code&gt;value&lt;/code&gt;<a name="line.235"></a>
<FONT color="green">236</FONT>         */<a name="line.236"></a>
<FONT color="green">237</FONT>        public void<a name="line.237"></a>
<FONT color="green">238</FONT>        init(final String name, final Object value,<a name="line.238"></a>
<FONT color="green">239</FONT>                                final Exporter export) throws Exception {<a name="line.239"></a>
<FONT color="green">240</FONT>            final ByteArray content =<a name="line.240"></a>
<FONT color="green">241</FONT>                output.serializer.serialize(export, Object.class, value);<a name="line.241"></a>
<FONT color="green">242</FONT>            final OutputStream out =<a name="line.242"></a>
<FONT color="green">243</FONT>                Filesystem.writeNew(Filesystem.file(root, name + output.ext));<a name="line.243"></a>
<FONT color="green">244</FONT>            out.write(content.toByteArray());<a name="line.244"></a>
<FONT color="green">245</FONT>            out.flush();<a name="line.245"></a>
<FONT color="green">246</FONT>            out.close();<a name="line.246"></a>
<FONT color="green">247</FONT>        }<a name="line.247"></a>
<FONT color="green">248</FONT>        <a name="line.248"></a>
<FONT color="green">249</FONT>        /**<a name="line.249"></a>
<FONT color="green">250</FONT>         * Creates a temporary override of a configuration setting.<a name="line.250"></a>
<FONT color="green">251</FONT>         * @param name  setting name<a name="line.251"></a>
<FONT color="green">252</FONT>         * @param value transient setting value<a name="line.252"></a>
<FONT color="green">253</FONT>         */<a name="line.253"></a>
<FONT color="green">254</FONT>        public void<a name="line.254"></a>
<FONT color="green">255</FONT>        override(final String name, final Object value) {<a name="line.255"></a>
<FONT color="green">256</FONT>            Filesystem.file(root, name);<a name="line.256"></a>
<FONT color="green">257</FONT>            cacheKeys = cacheKeys.with(namespace + name);<a name="line.257"></a>
<FONT color="green">258</FONT>            cacheValues = cacheValues.with(value);<a name="line.258"></a>
<FONT color="green">259</FONT>        }<a name="line.259"></a>
<FONT color="green">260</FONT>    }<a name="line.260"></a>




























































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